Reducing the Risks from Tectonic Hazards

• There are 4 main management strategies for reducing the risk from tectonic hazards: monitoring, prediction, protection, planning
• Monitoring: volcanoes

  All active volcanoes are now monitored using hi-tech scientific equipment including:

  • Seismometers (seismographs) to detect and record microquakes
  • Tiltometers to monitor ground deformation as magma rises
  • Instruments to monitor gas emissions and changes in water chemistry
• Monitoring: earthquakes

  Earthquakes generally occur without warning. But a network of seismometers monitor and record them
• Monitoring: earthquakes

  Tsunami monitoring systems in the Pacific and Indian Oceans use floating buoys to detect early tsunami waves following an earthquake. Warnings are then issued using sirens, TV and media alerts
• Prediction: volcanoes

  Monitoring is now allowing accurate prediction and effective evacuation
• Prediction: earthquakes

  Accurate predictions are impossible due to a lack of clear warning signs. But historical records can help identify locations at probable risk e.g. Istanbul on the North Anatolian Fault, Turkey
• Protection: volcanoes

  Earth embankments have been used to successfully divert lava flows (e.g. Mount Etna, Italy). In Japan, weirs and small dams control lahars (mudflows of ash and water)
• Protection: earthquakes

  Earthquake-resistant engineering of infrastructure and buildings is the best way to reduce risk e.g. seawalls
• Planning: volcanoes

  Hazard mapping is used to identify areas to control development in at risk areas, and plan evacuation routes (e.g. Mount Merapi, Indonesia)
• Planning: earthquakes

  Shakemaps (of past impacts) are used to identify lower-risk areas to locate high-value buildings (e.g. hospitals and power stations)